Jacking mechanism for seadrome



Aug. 2, 1960 E. T. YOUNG JACKING MECHANISM FOR SEADROME 4 Sheets-Sheet 1Filed June 28, 1954 mum-Eb-I INVENTOR. EINAR T. YOUNG ATTORNEYS FIG. 4.

Aug. 2, 1960 E. T. YOUNG JACKING MECHANISM FOR SEADROMB 4 Sheets-Sheet 3Filed June 28, 1954 RESERVOIR INVENTOR. EINAR T. YOUNG BY FIG. 7.

ATTORNE Aug. 2, 1960 Filed June 28, 1954 E. T. YOUNG JACKING MECHANISMFOR SEADROME 4 Sheets-Sheet 4 ATTORNEYS States "2341143 JA'CKINGMECHANISM non snAnnoME Einar T. Young, Newtown Square, Pa., assignor toSun Oil Company, Philadelphia, Pa., a corporation of New Jersey 9 FiledJune28, 1954, Ser; No. 439,589 reclaims. c1. 6'1 46.5)

example, where olfshore well drilling is to be performed, 7

may be solidly founded on the ocean bottom by self-docking apparatus inwater of depths up to and exceeding 80 feet.

The seadrome includes a plurality of buoyancy tanks framed into a trussstructure. The deck is mounted on the truss structure and is, forexample, adapted to support facilities and equipment necessary fordrilling operations such as a drilling derrick and rig, living quarters,storage area, power plants, mud and other liquid storage vessels, etc.Alternatively, the seadrome may be formed of a solid walled bargestructure which floats by virtue of its own displacement;

In addition to the foregoing, foundation columns are provided which areadapted to be jackeddownwardly into engagement with the ocean bottomwhereupon continued jacking will serve to raise the seadrome structure asuficient heightabove the surface of the water so that the structure isabove the level of waves normally encountered except during extremestorm conditions.

It is the primary object of this invention to provide apparatus forjacking the foundation columns downwardly and upwardly with respect tothe seadrome structure.

When it is considered that the seadrome structure may be approximately220 feet in length, 134 feet in width and may have a deck level normallyapproximately 28 feet above the surface of the water, and that theentire structure is jacked upwardly on the foundation columns so thatthe lower portion of the structure will be above the largest wavesnormally encounteredexcept possibly during extreme storm conditions, itwill be evident that the supporting columns will'be distributed over aconsiderable area of the ocean bottom which will, in many instances, beunlevel, and it will also be evident that synchronizing the liftingmovements of the jacking systems on each of the columns in order tomaintain not only a level seadrome structure during jacking but also tomaintain uniform load distribution over the columns during thesubstantial length of jacking involved in raising and lowering theseadrome must be considered.

2,947,148 Patented Aug. 2, 1960' 2 ments are housed in a singleenclosure in the location of the jacking elements and in'which theremaining portions of the apparatus involved in the electrical controlcircuit are housed in a control station which may, if desired, be remotefrom the mechanical jacking elements. These and other objects of theinvention will become apparent from the following description when readin} conjunction with the accompanying drawings, in which: Figure 1 is adiagrammatic perspective showing of the entire seadrome structure; 7Figure 2 is a fragmentary longitudinal section through a portion of afoundation column and a buoyancy tank showing the jacking apparatus; a iv Figure 3 is a section taken on the trace 33 shown in Figure 2; aFigure 4-is a vertical section through a fragmentary portion of theapparatus shown in Figure 2;

Figure 5 is a diagrammatic showing of the hydraulic circuit employedwith the jacking apparatus for each foundation column;

Figure 6 is a diagrammatieshowing of the electrical circuit employedwith the jacking apparatus for each foundation column; and. V,

- Figure 7 is a Vertical elevationpartly in section showing afragmentary portion of apparatus shown diagrammatically in Figure 1.

In Figure 1 there is shown generally at Z a perspective diagrammaticshowing of the complete seadrome structure. The seadrome structureincludes an open supporting truss structure 4 into which buoyancy tanks6 and 8 are framed. The buoyancy tanks 6 each extend upardly above anassociated buoyancy tank 8 and are a of lesser outer diameter than theirassociated buoyancy v tanks 8. Thus, there is provided astep 10 onwhich-the It is a further object of the invention to provide a jackingsystem by means of which, when all of the columns are resting on theocean bottom, the jacking of each of the columns can be commencedsimultaneously.

It is a further object of the invention to provide a truss structure 4rests. are of annular form and a foundation column 12 ex; tends througheach pair of buoyancy tanks. A foundation -tank 14 'is affixed to thelower end of each foundation column 12 and provides a footing for thecolumn on the ocean bottom. As will be evident by viewing the figure,the seadrome truss structure may be supported above the surface of thewater by the foundation columns when the foundation tanks are resting onthe ocean bottom. It will also be evidentthat while the figure shows sixfoundation columns the number and arrangement of buoyancy tanks andfoundation columns may be selected in accordance with the structuralproportions of any particular seadrome involved.

The seadrome truss structure is provided at one endv with a slot 16which is adapted to be positioned around' or above a drilling location.A platform may be mounted on the seadrome extending across the slot andbe adapted to support a conventional type of drilling derrick.Alternatively, a separate drilling platform may be mounted on pilings orother suitable structure fixed to the bottom of the ocean and a slot 16positioned around the StI'UC-rture While drilling operations'are beingconducted;

In Figure 2 there is shown a fragmentary section through a buoyancy tankand its associated foundation column. Between the upper buoyancy tank. 6and the foundation column 12 there are positioned two hydraulicallyoperated principal piston and cylinder type jacks 18' and 2h. The twojacks are positioned one above the 32 are aflixed to the outer wall ofthe foundation column The buoyancy tanks 6 andS 12 adjacent to the jacks;18 and 20. The upper end of the piston rod of the upper jack 18 isprovided with a clevis 34 within which there is pivotally mounted across pin having its ends 36 adapted to engage transversely alignedrecesses in the rack bar 30. The lower jack 20 is provided at the upperend of its piston rod with a clevis 38 within which'there is pivotallymounted a pin having its outer ends 40 adapted to engage thetransversely aligned pairs of recesses in the rack bar 30. V A guideroller 42 is rotatably mounted on a pin which is rotatably mountedbetween the brackets 24. The guide roller 42 is positioned to bearagainst the outer wall of the foundation column 12 A similar guideroller is desirably provided between the lower foundation tank- 8 andthe column 12. 1 V

It will be evident that four of the rack and jack ass'emblies thusfaidescribed aredesirably provided in association with each of thefoundation columns. In this manner the load transfer between theseadrome platform and the foundation columnis accomplished with adequateload distribution. If desired, additional guide rollers, suchasthe-rollers 42, may be provided intermediately of the various jack andrack assemblies in order to further insure the maintenance of thefoundation column in proper alignment with the buoyancy tanks. A supportpost 46 extending upwardly from the top of the buoyancy tank supports aswing or auxiliary jack 48 the base of the cylinder of which ispivotally mounted at 50 to the upper end of the support'post. A swingjack piston rod is pivotally connected at 52 to the upper end of thejack cylinder 18. A spring 54 is mounted between the end of the pistonrod and the cylinder 48 and serves to urge the piston rod outwardly,thus to move the jack 18 toward the rack 30.

, Within a recess 56 in the buoyancy tank 6 a swing or auxiliary jack 58is pivotally mounted to a suitable bracket at 60. The outer end of theswing jack piston rod is pivotally connected at 62 to the upper end ofthe jack cylinder 20. A spring 64 positioned between the outer end ofthe piston and the cylinder 58 serves to urge the swing jack 20 towardthe racks 30.

A case 66 is mounted on a plate 67 affixed to a framework 68 whichalsoserves to assist in supporting the post,46. Within the case 66 thereare mounted a plurality of limit switches responsive to the positions ofthe jacks as will be hereinafter described. These limit of pulleys 70and 72 mounted on concentric shafts extending out of the case 66. Oneend of a cable 74 is affixed to andextends partly around the peripheryof the pulley 70. The other end of the cable 74 is affixed to the pin36. One end of a cable 76 is afiixed to and extends partly around theperiphery of the pulley 72. The other end of the cable 76 is afiixed tothe pin 40. One end 'of a cable 78 is afixed to an arm 80 extending froma rotatable shaft 82 extending through the wall of the case 66. Theother end of the cable 78 is affixed to a pin 84 attached to andextending outwardly from the portion of the jack 20 adjacent to themounting pin 26. A bar 86 is affixed to and extends outwardly from thecylinder of jack 18. The outer end of the bar 86 is adapted to engage ablade 88 afiixed to and extending from a rotatable shaft 90 extendingthrough the wall of the case 66.

"Refen'ing to Figure 4, the pulleys 70 and 72 are mounted on concentricshafts 92 and 94, respectively. A shaft 92 is rotatably mounted in thewall of the case adjacent to the pulley 70 and terminates at 93 in aposition midway through the case. in the shaft 92 and extends through tothe opposite side of the case wherein it is rotatably mounted asindicated at 95. Cam segments 96, 98-and 100 are afiixed to the shaft 92and cam segments 102, 104 and 106 are afiixed to the shaft 94. A spring108 has its ends, affixed to the cam segment196 and the adjacent wall ofthe case. 'A

The shaft 94 is rotatably mounted second spring 110 has its ends affixedto the cam segment 106 and the adjacent wall of the case. The limitswitch 112 is mounted on a support bracket 114 and positioned so as tohave its-actuating roller 116 in engagement with the peripheral surfaceof the cam segment 96. Similar limit switches 118, 120, 122, 124 and 126are positioned to be responsive to motion of their associated camsegments 98, 102, 104 and 106, respectively. Limit switch 128 ispositioned to be responsive to motion of a cam segment 130 afiixed tothe rotatable shaft ,82. Limit switch 132 is positioned to be responsive to rotation of a cam segment 134 afiixed to the rotatable shaft90.

Expansion of the jack 18 will draw the cable 74 upwardly and causerotation of the pulley 70, the shaft 92 and the cam segments 96, 98 and100. Rotation of these segments will actuate their associated limitswitches 112, 118 and 120, respectively, as will be hereinafterdescribed. Upon contraction of the jack 18 the spring-108 will cause theshaft 92 to rotate maintaining tension on the cable 74 and rotating thecam segments to the degree allowed by the contraction of the jack 18.Similarly, contraction of the jack 20 will cause rotation of the pulley72 and thecam segments 102, 104 and 106. Expansion of the jack 20 willpermit the spring 110 to rotate the shaft 94 to the degree'allowed bythe expansion of the jack 20. Actuation of the swing jack 48 pulling thejack 18 away from the column 12 will cause the bar 86 to engage theblade 88, rotating the shaft 90 and actuating the limit switch 132.Actuation of the swing jack 58 will move the jack 20 away from thecolumn 12, moving the pin 84 downwardly thus pulling downwardly on thecable 78 and causing the shaft 82 to rotate resulting in actuationof'the limit switch 128.

As has been previously stated, the apparatus described in conjunctionwith Figures 2, 3 and 4 represents one set of jack cylinders andassociated limit switches. In order to provide for the most desirable.jacking conditions, four sets of jacking cylinders and associated limitswitches are desirably provided with each column. The hydraulic andelectrical control systems employed with the four sets of jack cylindersassociated with a single column will now be described. In Figure 5 thereis shown a hydraulic pump which pumps hydraulic fluid from a reservoir142 into a supply line 144 at a pressure determined by the setting of apressure relief bypass Valve 146. This pressure is indicated by aconventional pressure gauge 148.

Four solenoid operated hydraulic control valves 150, 152, 154 and 156are connected to the supply line 144 and are connected to a return line158. Conventional throttling valves may be employed in the supply andreturn line connected to these valves if desired. The valve is connectedthrough lines 160 and 162 to the cylinders of the upper jacks 18. Theline 160 is connected to the jack cylinders so as to provide supplyliquid for expanding the jacks and the line 162 is connected to the jackcylinders so as to supply liquid for contracting the jacks. It will beevident that, while only two jacks are shown in the drawing, any numberof jacks may be connected in parallel arrangement, as indicated by theconstruction line 164 breaking 01f the drawing.

,The valve 150 is a three position valve having springs 166 forcentering the valve in a completely shut-off condition and havingsolenoid coils 168 and 170 for positioning the valve in either of itstwo operative positions. When the valve is deenergized it will assumethe position shown with all of the hydraulic lines closed off. If thecoil 168 is energized, the valve will assume a position in whichhydraulic fluid under pressure is supplied to the cylinders of the jacks18 to expand the jacks and, if the solenoid coil 170 is energized, thevalve' will assume a position in which hydraulic fluid pressure issupplied to'the cylinders of the jacks 18 in I s'uch a manner .as tocause contraction. of thejacksl The electricalcontrol circuit forenergizing the solenoidcoils 168 and 170 will be hereinafter described;

The Valve 152 is connected through line 172.to the cylinders of theswing jacks 48 The line is connected to the swing jack cylinders so asto supply liquid for contracting the jacks. The control valve 152 is atwoposition valve having a return spring 174 normally urg ing the valveto assume a position in which the line 172 is connected to the returnline 158. The valve includes a solenoid coil 176 which, when energized,causes the valve to assume a position in which hydraulic fluid underpressureis delivered to the line 172 and causeslthe swing jack cylinders48 to be contracted.

The control valve 154 is connected to the jack cylinders of the lowerjack through lines 178 and 180. The line 178 is connected to the jackcylinders so as to supply liquid for expanding the jacks and the line180 is connected to the cylinders so as to supply liquid for contractingthe jacks. The valve 154 is a three-position valve identical to thevalve 150 and is provided with two solenoid coils 182 and 184. When thecoil 182 is energized, the valve is positioned so as to deliverhydraulic fluid under pressure to the cylinders of the jacks 20 so as toexpand the cylinders, and when the coil 184 is energized the valvedelivers fluid-under pressure to the cylinders 20 so as to causecontraction of the cylinders.

When neither of the coils 182 or 184 are energized, the

valve will assume a neutral position in which all of the hydraulic linesare shut off.

The valve 156 is connected through line 178 to the cylinders of theswing jacks 58. The valve is so at" ranged that when the coil 183 isdeenergized the valve straits is positioned by the spring 181 and theline 178 is connected to the drain line 158. When the coil 183 isenergized, the valve is positioned so as to deliver hydraulic fluidunder pressure to the cylinders of the swing jacks 58.

The two swing jacks 48 and 5S and their associated springs 54 and 64 areso arranged that when no fluid pressure exists in the swing jackcylinders their associated springs urge the jacks 18 and 20 intoengagement with the rack 30. When either of the swing jack cylinders isreceiving oil under pressure, the piston in the cylinder is retractedand-acts to compress its associated spring and draw its associated jackcylinder out of engagement with the rack 30. a

' In Figure 6 there is shown the electrical diagram involved in thecontrol systememployed for controlling the operation of four sets ofjack cylinders associated with a single column. The control circuitincludes a plurality of relays, the coils of which are indicated at R1,R2, R3, R4, R5, R6 and R7, and their associated only one switch 120 andone. switch 122, which are actuated at the mid points of the strokes ofthe jacks 18 and 2 0,respectively, are required for the control systemassociated with each column.

The coil of the relay R7 is connected in series with a push button 196between a pair of conductors 199 and 192 which are connected to asuitable source of power. The push button 196 is manually controlled andis of the type which must be held closed by an operator. The coil of therelay R6 is connected in series with a second push button 194 betweenthe power lines 198 and 192. The push button 194 is also of the typewhich must be held closed by an'operator. The push button 196 serves toinitiate operation of the control system through a cycle which iseifective to move the column upwardly with respect to the seadromeplatform and the push button 194 initiates operation of the controlsystem through a sequence of operations elfective to lower the columnwith respect to the seadrome structure. These sequences of operationswill be hereinafter'described. A normally open relay 6 contact R6-1 isconnected between the conductor 190 and a conductor 198. A similar relay7 contact R7-1' is connected between the conductor 190 and the conductor198.

The coil of relay Rl is connected in series with a' series arrangementof the contacts of limit switches 112 between the conductors198 and 192.The contacts 112 are closed when the jack 18 is in an expanded or upperposition. Thus, when all four of the jacks 18 have reached theiruppermost positions, the four contacts 112, 112, 112" and 112" will beclosed and the coil of the relay R1 will be energized if contact 194 orcontact 1% is closed. The normally open relay contacts 122-1 and R3-1are connected in parallel arrangement and in parallel arrangement withthe four limit switch contacts 112.

One side of the relay coil R2 is connected to the con ductor 192. Theother side of therelay coil R2 is connected to a parallel arrangement ofthe limit switch contacts 118. The limit switch contacts 118 are openwhen switch contacts 124 are open when the lower jack Ztiis contactsindicated at R1-1, etc. The relay R5 is a time delay relay ofconventional type in which operation is delayed for a two secondinterval after it is energized. The circuit also includes a pair ofsingle pole double throw switches 240 and 246, a pair of interlockedsingle pole three-position switches 200 and 204, and a second pair ofinterlock three-position single pole switches 220 and 224. The coils ofthe solenoids associatedwith the hydraulic valves 158, 152, 154 and 156described in connection with Figure 5 are indicated at 176, 18.3, 168,

170, 182 and 184 in the wiring diagram. Also included in the wiringdiagram are the contacts of the various limit switches described inconnection with Figure 4. Except for switches 120 and 122, thearrangement shown in Figure 4 is the arrangement of limit switches"associ ated with each of the four sets of jacks associated with eachcolumn. Thus, in the wiring diagram of Figure 6, there are shown thevarious sets of four contacts-having identifying numerals correspondingwith the numerals of the limit switches shown in Figure '4. Thesecontacts are distinguished bytheir primenumbers as each' beingassociated with one of the four sets of jacking cylinders. As will behereinafter described more fully,

expanded to its upper position. The other sides of the contacts 118 and124 are connected through a series arrangement of normally open contactsR1-1 and R4-1 to I the conductor 198.

One side of the coil 176 of the solenoid-valve 152 controlling the swingjack 48 is connected to the conductor 192. The other side of the. coil176 is connected to the movable arm of the single pole double throwswitch 240. When the switch 240 is positioned on the contact 242, thecoil 176 is connected directly across the power lines 190 and 192. Whenthe switch 240 is connected to the contact 244, the coil 176 isconnected to the movable arm of a single pole doublethrow switch arm 122positioned to close with contact points 121 or 123. Contact 121 isconnected in series with one side of a normally open contact R6-3. Thecontact 123 is connected in series with one side of a normally closedcontact 116-4. The other sides of the contacts R6-3 and R6-4 areconnected together and through four limit switch contacts 128 'toconductor 198. The limit switches 128 are closed when the jack 20 is inengagement with the rack.

One side of the coil 183 of the hydraulic control valve 156 controlilngthe flow of hydraulic fluidrto the lower swing jack' 58 is connected tothe line 192. The other 7 side of thexc'oil 183 is connected to themovable arm of coil 183 is connected .to the movable arm of a singlepole double throw switch positioned to close'with contact points117 or119. The contact 117 is connected in series with one side of a normallyopen contact R7-3,

and are provided with only one of the jacking assemblies with eachcolumn. These two contacts change their positions at approximately thehalf-way point-of the jack strokes. The contact 122 moves to the contactpoint 123 when the contracting jack 20 passes to the'lower half of itsstroke. The contact arm 120 switches to the contact point 117 when thecontracting jack 18 passes to the lower half of its stroke.

One side of a normally closed contact R 1 of the time delay relayis'connected to the junction between the relay coil R3 and the'switchcontacts 124. The other side of the contact R5-1 is connected to aparallel arrangement of normally open contacts R6-2 and R7-2. The otherside of the contact R6-2 is connected between the contacts 132 and thecontact R73. The other side of the contact R7-2 is connected between thecontacts 128 and the contact R63.

One side of the relay coil R4 is connected to the line 192. The otherside of the relay coil R4 is connected through the series of arrangementof the contacts 126 to the conductor 198. The parallel arrangement ofnormally open relay contacts R2-2 and R3-2 is connected in parallel withthe series arrangement of contacts 126.

The relay contacts 126 are closed when the jack 20 is contracted to itslowermost position.

The coil' of the time delay relay R5 is connected directly across theconductors 192 and 198. Thus,.upon depression of either of the'pushbuttons 194 and 196, the coil R5 is energized and the contact R5-1remains closed for approximately two seconds and is thereafter opened.

One side of the coil 168 of the hydraulic control valve 150 is connectedto the line 192. The other side of the coil 168 is connected to themovable arm of the single pole three-position switch 200. When theswitch 200 is in contact position 208, the coil 168 is isolated from thecircuit. When the contact 200 is positioned on the contact point 212,the coil 168 is connected directly across the power lines 190 and 192.In this position, operation of a control valve is manually controlled bythe switch 200. When the switch 200 is positioned on the contact 210,the coil 168 is connected through the normally closed contact R1-2 tothe conductor 198. Similarly, one side of the coil 170, which is theother coil of the hydraulic control valve 150, is connected to the line192, and the other side of the coil 170 is connected to the movable armof the switch 204; When the switch 204 is on contact position 218, thecoil 170 is isolated from the circuit. When the switch 204 is on contact214, the-coil 170 is connected directly between the line 190 and theline 192. When the switch 204 is connected to the contact 2 16, the coil170is connected through the normally open relay contact R2-3 toconductor 198. The

interlock, indicated at 206, is provided to insure that when either ofthe coils 168 or 170 is connected directly across power supply the othercoil is isolated from the circuit. j

One side of each of the coils 182 and 184 of the hydraulic control valve154 controlling thelower. jack 20 is connected to the line 192. Theother side of thejcoil 182 is connected to the movable arm of switch220., When the switch 220 is positioned on contact 228, the,

coil 182 is isolated from the circuit. When the arm 220 is positioned oncontact 232, the coil 182 is connected directly across the power lines190 and 192. When the arm 220 is positioned on the contact 230, thecoil182 is connected through a normally open relay contact R3-2 to theconductor 198; The otherside' of the coil 184 is connected to contact toarm 224. When the 'contact arm 224 is positioned on the contact 238, thecoil 184 is isolated from the circuit. When the arm 224 is positioned oncontact 234, the coil 184 is connected directly across power lines and192. When the contact arm 224 is positioned on the contact 236, the coil184 is connected through a normally closed contact R4-2 to the conductor198. ;The interlock arrangement, indicated at 226 be tween the contactarms 220 and 224, is provided to insure that when either of the contactarms is positioned to con nect its associated coil directly across thepower lines, the other coil is isolated from the circuit.

,During normal operation'of'the jack system, the arm 20%) is positionedon contact 210, the arm 204 is positioned on contact 216, the arm 220 ispositioned oncontact 230 and the arm 224'is' positioned on c'ont'act236;With these arms in these positions, the relays R1, R2, R3 and R4 controloperation of the hydraulic control valve solenoid coils 168,170, 182 and184, respectively. The coils 176 and 183 of thehydraulic control valvedelivering hydraulic fluid to the swing jack members are controlled byrelays R6 and R7 and by the limit switch contacts 128 and 132 which areopen when the jacks 20 and the jacks 18, respectively, are in engagementwith their associated racks.

Before proceeding further with adescription of the operation of thecontrol'system, it should be noted'that the active stroke of the jackshas been selected to be ten inches. This stroke length is controlled, ofcourse, by the setting of the various limit switches. Thus, when one'ofthe jacks is in'engagement with the rack, it will move the rack for adistance of ten inches and, when one of the jacks is disengaged from therack, it will move for a distance of ten inches with respect to the jackmounting but will move a distance of twenty inches with respect to therack which is being moved ten inches by the other jack. It should alsobe noted that while the jack stroke is ten' inches the pitch of the rackrecesses 32, as indicated at 31, is sixteen inches. The sixteen inchpitch allows jack motion suflicient to provide jack travel into thesocket forming portions 33 of the rack recesses.

During the operation of a jacking cycle, the two jacks will both beengaged in the rack recessesonly for those time intervals for which theone jack'is fully expanded and the other jack is fully contracted, orvice versa. The remainder of the time when one jack is in engagementwith the rack and is moving the rack in one direction, the other jackwill be disengaged from the rack and will be moving inthe-opposite'direction.

Referringnow to the wiring diagram of Figure 6 and assuming that it isdesired to raise the seadrome platform with respect to the supportingcolumns, the push button 194 is closed to initiate the sequence ofoperation of the control system which will serve to move the columndownthe rack and thus the solenoid coil 183, is deenergized.

Relays R1, R2, R3 and R4 remain dcenergized because of the positions oftheir associated series contacts as shown in Figure 6. 'The solenoidcoil 168-isenergized through relay contact R1-2 and the solenoid coil184 is energized through 'relay contact R4-2. Thus hydraulic fluid underpressure is fed to the upperjacks'18 in such ajdirection as to expandthe jacks and hydraulic fluid under pressure is fed tothe lower jacks 20in such a direction as to contract the jacks.

column.- When all four of thelower jacks20 are fully contracted, thefour limit switches126'will close, energizing-the relay R4; Closure ofthe relay 'R4 will deener- Contraction of the' 'jacks 20 will raise theseadrome withrespect to the .gize the Selene-M184 permitting thehydraulic control valve 154 toassume aneutralposition with all of thehydraulic lines shutoff; Prior to completion of the contraction of eachof the lower jacks 20, each .of the upper jacks 18 will become fullyextended and will have dropped into a rack recess 32 in response to theurging of the swing jack springs 54. When the four upperjacks 13 areeach in engagement with a rackrecess, the fourlimit switches 132. willbeclosedandrthe solenoid coil 183 will be energized through the relay-contact.R7-4 and the switch am 1.20. Closure of this contact positionsthe hydraulic contro1'valve156 so ast o supply fluid under pressure tothe swing jacks, 58 urging the lower jacks 2% out Qf'611'.

gagerhentfwith the rack. At this time, however, the pins 40 of'thejacks20 areengaged inthe sockets 33 of the racks preventing the jack frombeing retracted.

When the upper jacks 18 reach their uppermost position, I the limitswitches 112 are closed and the relay R1 isenergiZed, and contact R1-2opened, deenergizing the solenoid coil 168 of the control valvelEtl,this permitting the control valve 150; toassume a neutral position withall of theiconnections shut ofi'. Uponclosure of the relayfcontactsRl-landR4-1, therelay coils R2 and R3 are energized through limit switches1'18 and 124, respectively, whereupon relay coil R1 is connected topower through relay coilsRZ-l and R341. 7

Thus when the lower jacks 20 are in their lowermost positions and whenthe upper jacks 18 are in their uppermost positions and engagedwiththe'rack's, the relays R1, R2,;R3. and R4 are all energized and thesolenoid valve coil 168 is deenergized and the coil 17% is energizedthus positioning the hydraulic control valve 159 so as to move the upperjacks 18v downwardly, Solenoid coil 182] is energized and solenoid coil1% is deenergized thus positioning the hydraulic control valve 154 tomove the lower jacks 20 upwardly. As the upper jacks move ,downwardly,the; column is moved downwardly with'r'espect to the 'seadrome platform.As the lower jacks 2t} move upwardlyptheirpins 40 become disengaged fromtheir associated sockets 33 in the racks and the swing cylinciers 58pull the lower jacks 20 out of engagement with. the racks. The upperjacks lttcontinue to contract drawing the column downwardly and thelower jacks continueto expand while disengaged from the racks until theyeach pass the midpoint positions in their respective strokes atwhichtime the contacts 120 and 122 shift and the. contact 122 moves tocontact point 121 and the contact 120 moves ,to contact point 117; Thismovement of the contact'120 deenergizes the solenoid coil 183 of thehydraulic control valve 156 draining the hydraulic 'iluid from the swingjacks 58 and permitting the springs 64 to urge the lower .jacks 20 intoengagement with their racks. As the lower jacks 20 continue to expand,they ultimately reach the next rack recess and drop into engageinenttherewith. At approximately the same time this occurs, the upper jackslShave reached the lowermost portions of their strokes. i i

When the lower jack cylinders 21] move into engage ment with the rackrecesses, limit switches 128 close and the solenoid coil 176 of thehydraulic control valve 152 is energized through the closed contactR6-3. This actuates the valve 152 so as to deliver hydraulic fluid underpressure to the swing jack 48 to urge the upper jack 1% out ofengagement with the racks.

At this point in-the cycle when the upper jacks 18 are in theirlowermost positions and thelower jacks 29 are in their uppermostpositions, the switches [118 and 124 are open-and therelay'coils RZandR3 are deenergized. Furthermore, the limit switches 112 are only closedwhen the jacks 18a1fe in their uppermost position and, therefore, inthis point in the cycle, the relay'coil R1 is denergizedfl Additionally,the limit switches 126 are only closed when the lower jacks 20 arecontracted.

Thus," at this point in the cycle, the limit switches 126 are open, thecontact R24 is open and the contact R3-2 i s-open. Thus the relaycoil R4is deenergized. With the relay coils R1, R2, R3 and R4 deenergized, thejacks 18 are moved upwardly and the jacks 20 are moved downwardly. Uponcommencement of the upper motion by the jacks E8, the pins 36 of thejacks move clear of the sockets inthe racks and the swing jacks 48 movethe cylinders out ,ofengagement with the racks.

The jacks now continue to move with the jacks: 18 expanding while out ofengagement with the racks and the jacks 20 contracting while inengagement with the racks. The jacks cross the mid-points of theirstrokes and the switches 122 and 120 again shift and the coil 176 isdeenergized permitting the spring 54 to urge the upper jack cylinders 18back into engagementwith the racks. Thus a cycle of operation has beencompleted. .Ihese cycles of operation will continue in sequence untilthe push button 194 is open.

The time delay relay R5 and its contact R5-1 are provided in order thatthe cycle of operation will start in the proper direction regardless ofjack position. Thus with the jacks in position as shown in Figure 2, ifthe push button 196 is closed, the relay R7 is energized and the coil R3is immediately energized through the circuit formed by the limitswitches 128, the contact R7-2 and the contact RS- I. The coils R1 andR2 are also energized and the coil R4 is energized. Thus substantiallyimmediately upon the depression of the down button 196, the four relaysR1, R2, R3 and R4 are each energized and each of the jack cylindersimmediately begins movement in the operates and the contact R5-1 opensand remains open until the sequence of operation is interrupted by therelease ofthe button 196. I

It is believed unnecessary to burden this disclosure with a recitationof the sequence of operation of the control circuit when eachof the pushbuttons 194 and 196 is depressed at any possible point in the operatingcycle. It should be noted, however, that the arrangement of limitswitches 128 and 132 prevent both of the swing jack solenoid controlvalves l52 and 156 from being operated simultaneously. However, theswitches 240 and 246 permit manual operation of the swing jacks 48 and58 if desired. The interlocked switches 200 and 204 permit manualoperation of the upperjacks 18 and the interlocked switches 220 and 224permit manual operation of the lower jacks 2t The up and down pushbuttons 194 and 196 are provided in the form shown in order that-it isnecessary for an operator to hold the buttons closed manually during thejacking of any one column. This. type ofdead man control is provided toprevent the possible occurrence of unattended operation of the jackingsystem. The conductor 262 is connected between the up button 194 and therelayR6 and a conductor264 is connected between the down button 196 andtherelay R7. These two connections are provided in order that thecontrol circuit for operating the jacking system at one column may beconnected to a master point at whichpoint the jacking systems of each ofthe columns on the seadrome may be centrally controlled if desired. Thiscentral control permits at a central station a control of all of thejacking systems in response to inclination or load indicating means inorder that the jacking of all or the columns of the seadrome may becoordinated in such a manner that the load is sufiiciently uniformlydistributed among the columns during jacking and that the seadrome ismaintained 7 one column as a result of greatly unbalanced loadings amongthevarious columns, it will be evident that lifting 11 of the jackingsystem of that one column will be arrested untillsuch time as the loaddistribution among the various columns becomes more uniform as a resultof continued jacking of the other columns.

Heretofore, it has been noted that a convenient length of active jackstroke of ten inches has been selected. If the actual stroke of the jackcylinders is, for example, twenty inches, there is provided ampleoverrun at each end of the normal active stroke in which unbalanced'loadconditions, such as might arise very rapidly in emergency conditions,may be compensated for through the pressure relief valves 146. Thetwenty inch stroke of the cylinders provides an additional desirablefeature in that in the event ofmaloperation of one of the jacksresulting in the jack cross pins failing to engage the rack thatparticular jack may be operated manually and placed into engagement withthe nearest rack recess even though this jack position be displaced fromthe normal jack position with regard to the positions of the other jacksof that column.

From the foregoing it will be evident that the jacking system describedserves to commence the jacking of the columns immediately upon thedepression of the up or down switches 194 and 196, respectively. It willfurther be evident that the system provides for an inherent loadbalancing and additionally admits of operation of the various columnjacking systems from a remote central 7 member, a body member havingsaid column member extending therethrough, said members being movablevertically relative to one another, and means operable for moving one ofsaid members selectively upwardly or downwardly relative to the othermember including rack means fixedly mounted upon said column member andextending longitudinally thereof, a first pair of extensible fluidmotors mounted directly upon said body memher for swinging movementrespectively about horizontal control station at which station apparatusfor indicating the level of the seadrome structure may be provided. I

Apparatus for indicating'the level of the seadrome structure is shown inFigures 1 and 7. It will be evident that a structure the size of theseadrome structure described herein will suffer a certain amount ofdeflection if the loading at the various columns is non-uniform. Thisproblem will exist in a solid barge type structure as well as in thetruss type structure disclosed. The level indicating system which ishereinafter described may be employed with any type of seadromestructure to indicate the relative elevations of the structure adjacentto each of the support columns.

In Figure 1 there is shown adjacent to each of the columns 12 acontainer 270. Pipe lines 272 extend between each of the containers to acentral station 274. At the central station each of the pipe linesterminate in a vertically extending tube 278 as indicated in Figure 7.Each of the containers 270 is provided with liquid as indicated at 280,the level of which is adjusted with regard to some predetermined portionof the seadrome structure in the vicinity of its associated column. Itwill be evident that if the level of the liquid in each of thecontainers is adjusted to be related to similar predetermined portionsof the seadrome structure adjacent to each column the levels 282 of theliquid in the upturned ends of the various pipe lines connected to thecontainers 270 will indicate at the central station the degree ofdeviation from level of these various portions of the seadromestructure. The capacity of each of the containers 270 is selected to besuch that the quantityof liquid in each of the containers is great withrespect to the variation in the quantity of' liquid occurring in itscorresponding tube 278. Thus only negligible errors will be introducedin the indications of level provided by the tubes 278 at the centralcontrol station as a result of displacement of liquid into or out of Vprevent the occurrence of excessive load unbalance among the variouscolumns. a e

It should be noted that the use of the seadrome is not limited to use atsea and that when the word sea is axes and detachably engageable withsaid rack means for transmitting a downwardly acting load from one ofsaid members to the other member, and means for controlling theextension and contraction and positioning of said motorsin'predetermined sequence and eflecting operation thereof in repeatedcycles whereby to controllably shift one of said members verticallyrelative to the other member selectively upwardly or downwardlyincluding a second pair of extensible fluid motors mounted directly uponsaid body member for swinging movement about horizontal axes andoperable for swinging said first pair of motors respectively about theirpivotal axes thereby to position each motor in detachable loadsupporting engagement with said rack means While the other motor is freeof said rack means.

) 2. The combination defined in claim 1 wherein each motor of the firstpair thereof is disposed in an upright position, each motor of thesecond pair thereof is disposed in a horizontal position and pivotallyconnected to the associated one of said first pair of motors, and theaxes of the pivotal connections of said first pair of motors to the bodymember and of said second pair of motors respectively to said first pairof motors are all paralleltoone another.

3. The combination defined in claim 2 wherein one motor of the firstpair thereof and its associated motor of the second pair thereof aredisposed in vertically spaced relation to the other motor of said firstpair" the same rack face.

operatively interconnecting said limit switches with said motors foractuation of said limit switches in response to extension, contractionand swinging movements of saidmotors.

6. The combination defined in claim 5 wherein the I electric circuitincludes switch means operable for 'permitting manual operation of themotors.

7. The combination defined in claim 5 whereineach motor of the firstpair thereof is adapted for actuating one of the limit switches when itengages therack means, and the motor of the second pair thereofassociated with the other motor of the first pair thereof is actuated inresponse to actuation of said switch for freeing the other motor of saidfirst pair thereof from the rack means.

8. The combination defined'in claim 1 wherein the fluid motors areconnected in a hydraulic circuit including a pair of valves operable forcontrolling the flow of pressure fluid respectively to the first pair ofsaid 13 motors, each of said control valves has two valve positioningcoils, and the latter are connected in an electric circuit includingrelay means operable for energizing said coils thereby to position saidvalves for supplying fluid pressure for selectively extending andcontracting said motors. 1

9. The combination defined in claim 1 wherein the fluid motors areconnected in a hydraulic circuit including valves operable forcontrolling the flow of pressure fluid respectively to said motors, eachof said control valves associated with one of the motors of the firstpair thereof has two valve positioning coils, and the latter areconnected in an electric circuit including relay means operable forenergizing said coils thereby to position said valves for supplyingfluid pressure for selectively extending and contracting said motors,switch means for initiating an automatic cycle of operation for shiftingone of said members selectively upwardly or downwardly relative to theother, and time delay means for ensuring shifting of said member in theselected direction regardless of the positions of said motors when saidshifting commences.

10. A seadrome comprising a plurality of laterally spaced upright columnmembers, a floatable platform structure having said column membersextending freely therethrough, said platform structure and columnmembers being movable vertically relative to one another, and meansoperable for moving said columns selectively upwardly or downwardlyrelative to said platform structure including rack means fixedly mountedrespectively upon said column members and extending longitudinallythereof, two groups of principal extensible fluid motors mounteddirectly upon said platform structure for swinging movement respectivelyabout horizontal axes and detachably engageable with said rack means fortransmitting column loads to said platform structure when said columnmembers are not engaged with the ocean bottom.

and for transmitting platform loads to said column members when saidcolumn members are engaged with the ocean bottom, and means forcontrolling the extension and contraction and positioningof saidprincipal motor groups in predetermined sequence and efiecting operationthereof in repeated cycles to controllably shift said column membersselectively upwardly or downwardly relative to said platform structureincluding two groups of auxiliary extensible fluid motors mounteddirectly upon said platform structure for swinging movement abouthorizontal axes and operable for swinging said groups of principalmotors respectively about their pivotal axes thereby to position eachprincipal motor group in detachable load supporting engagement with saidrack means while the other principal motor group is free of said rackmeans..

11. The combination defined in claim wherein the fluid motors areconnected in hydraulic circuit, electrically actuated valves areconnected in said circuit to control fluid flow, said valves areconnected in electric circuit with limit switches mounted upon saidplatform structure adjacent to said motors, and means is providedoperatively interconnecting said limit switches with said motors foractuation of said limit switches in response to extension, contractionand swinging movements of said motors.

12. The combination defined in claim 11 wherein the electric circuitincludes switch means operable for permitting manual operation of themotors.

13. The combination defined in claim 11 wherein each principal motor ofeither group thereof is adapted for actuating one of the limit switcheswhen it engages the rack means, and the auxiliary motor associated witha principal motor of the other group thereof is actuated in response toactuation of said switch for freeing the principal motor of said othergroup thereof from the rack means.

14. The combination defined in claim 10 wherein the fluid motors areconnected in a hydraulic circuit including a pair of valves operable forcontrolling the flow of pressure fluid respectively to the two groups ofprincipal motors, each of said control valves has two valve positioningcoils, and the latter are connected in an electric circuit includingrelay means operable for energizing said coils thereby to position saidvalves for supplying fluid pressure for selectively extending andcontracting said groups of motors.

15. The combination defined in claim 10 wherein the fluid motors areconnected in a hydraulic circuit including valves operable forcontrolling the flow of pressure fluid respectively to said groups ofmotors, each of said control valves associated with a principal motorgroup has two valve positioning coils, and said coils are connected inan electric circuit including relay means operable for energizing saidcoils thereby to position said valves for supplying fluid pressure forselectively extending and contracting said motors, switch means forinitiating an automatic cycle of operation for shifting said columnmembers selectively upwardly or downwardly relative to said platformstructure, and time delay means for ensuring shifting of said columnmembers in the selected direction regardless of the positions of saidgroups of principal motors when said shifting commences.

References Cited in the file of this patent UNITED STATES PATENTS2,308,743 Bulkley Ian. 19, 1943 2,334,992 Crake Nov. 23, 1943 2,407,796Page Sept. 17, 1946 2,558,401 Voigt June 26, 1951 2,540,679 LatfailleFeb. 6, 1954 2,673,064 Patterson et a1. Mar. 23, 1954 2,764,133 PegardSept. 25, 1956

